This will be no longer true (if it's possible to say it that way).
Some commercial software creators have detected, that (for some
unexplainable reason) a lot of their customers don't want to be forced
to one of RHEL or SLES. So many future commercial software (I expect
first versions with this new prerequisites) will have some concrete
dependencies (like kernel 2.6.16, glibc-2.6.xx, ...) and no
distribution. This means, that it's tested on the Linux distribution
the test team likes most - or (depending on the time and money
available for the test) for the bigger 4+ distributions.
I don't know how often out Linux emulation will be adapted, but if
this is seen as a chance, I suggest it should be used.
Jens